Shrimps' eye-rolling behaviour could end up in robots

If you should ever see a mantis shrimp rolling its eyes, that doesn't mean it's exasperated. Instead, it may simply be utilizing its polarization vision. That's what scientists at the University of Bristol have determined, and their findings could have applications in fields such as robotics.

In the Bristol study, however, it was discovered that in order to improve the perceived polarization contrast of objects, they roll their eyes up or down as needed. This brings a line of photoreceptors within their eyes into alignment with the angle of polarization of linearly polarized visual stimuli.

"We have known for a while that mantis shrimp see the world very differently from humans," says Dr. Nicholas Roberts. "They can use 12 different colour channels (we use only three), and can see the polarization of light. But the eye movements of mantis shrimp have always been something of a puzzle. Intuitively, a stable eye should see the world better than a mobile one, but mantis shrimp seem to have found a different way to see more clearly."

It is now hoped that the shrimps' eyes could inspire low-power robotic visual systems for applications such as underwater exploration or materials analysis.